#include <stdio.h>

int main()
{
	// 0xAB12  0234   123123  0B101010;
	'A'  'B'  '8'
	
	char a1;   1
	short a2; 2
	int a3;  4
	long a4; 32 4  64  8
	long long a4;  8

	int score = 0;
	int year = 0;
	int hour = 0;
	int min = 0;
	int sec = 0;

	min = sec;  
	min = 7;
	min = min+10;


	int a = 0, b = 0, c = 10, d = 100;


	printf("hello world%d %c %s %f\n",min );

	scanf("%d", &min);

	a++;   a = a+1;
	a--;   a = a-1;

	a++;
	++a;

	+ - * (float)a/(float)b %  
	>  <  >=  <=  !=  ==  
	&&  ||  !
	=  a = b;   a+=b  a = a+b;   a-=b  a = a-b; ...

	return 0;
}
